One of the key traits that distinguish temperate annual plants from perennial plants is developmental arrest resulting from vegetative and floral bud dormancy. This single trait is an essential developmental event crucial to the survival of perennial plants during periods unfavorable for growth, such as those encountered during winter. Bud dormancy induction and release is an important developmental problem and little is known about the genes and mechanisms that regulate this developmental process. A prerequisite to bud dormancy is the initiation and development of a bud. Studying bud development and dormancy provides a unique opportunity to unravel genetic and epigenetic factors and mechanisms for both plant and animal adaptation. Besides advancing our understanding of basic tree biology, knowledge of the genetic basis of bud dormancy may uncover novel regulatory mechanisms that will contribute to our general understanding of biology.
Trees are a major part of the terrestrial ecosystems yet research in the basic biology of tree growth and development has lagged behind that of herbaceous plants largely due to the challenges associated with conducting research in trees. Research of certain traits important to tree growth and development can not be performed with annual plants such as Arabidopsis, rice or maize for the simple reason that these model annual plant species lack these developmental processes. Bud dormancy is such a trait. Because of the fundamental importance of bud dormancy to adaptation, it has been studied for decades, yet we still lack an understanding of the underlying genetic and molecular mechanisms regulating vegetative bud development, dormancy and dormancy release.
Recently, the forest tree species Populus (poplar and cottonwoods) has been successfully used as a model for tree biology. The availability of a tree model in combination with the state of the art in molecular biology, genetic engineering and a variety of other disciplines have now made possible the scientific breakthroughs responsible for the present invention.